My Science School

Scientists send spacecraft to probe objects in space. These spacecraft carry instruments that help them take pictures and collect data in space and send them back to Earth. But to do this, the spacecraft needs electricity So what powers it?

Based on the mission it is assigned, and factors such as where the spacecraft is travelling, what it plans to do there and how long it needs to work engineers choose the best way to power a spacecraft.

The Sun                     

One source of power engineers consider is energy from the Sun, or solar power. Spacecraft that orbit close to Earth are dose enough to the Sun to use solar power. These spacecraft are fitted with solar panels, which convert the Sun's energy into electricity. The electricity from the panels charges a battery in the spacecraft and can be used even when the spacecraft doesn't have direct sunlight

Batteries

Sometimes, when the mission is only for a short duration, such as the Huygens probe that landed on Titan, Saturn's largest moon, and meant to work only for a few hours, engineers may power the spacecraft with batteries. These batteries are designed to be tough since they need to withstand the harsh environment of space.

Atoms

An atom is a tiny building block of matter. Atoms need to store a lot of energy to hold themselves together. However, atoms such as radioisotopes are unstable and begin to fall apart. As they fall apart, they release energy as heat. A radioisotope power system uses the temperature difference between the heat from the unstable atoms and the cold of space to produce electricity. This system produces power for a very long time even in harsh environments. That's why this system has been used to power many of NASA's missions, including the two Voyager spacecraft that continue to send back information after over four decades in space.

Picture Credit : Google

Ever wondered about the weather in space? Before that, let's think about what dictates the weather on our planet. The Sun, which is our source of energy, plays a titular role in governing the weather on Earth. And so does it create the weather in space! The activities on the Sun's surface can lead to a type of weather in space and this is called space weather.

Space weather is dependent on activities and changes on the Sun's surface such as coronal mass ejections (eruptions of plasma and magnetic field structures) and solar flares (sudden bursts of radiation). We are shielded from these bursts of radiation and energy by Earth's magnetosphere, ionosphere, and atmosphere.

Impact of space weather

The Sun is some 93 million miles away from our Earth. Yet, space weather can affect us and the solar system. The electric power distribution grids, global satellite communication, and navigation systems are all susceptible to conditions in space that are impacted by the Sun.

Space weather can damage satellites, affect astronauts and even cause blackouts on Earth. Such incidents are rare but they have happened before.

CME, solar flare

When a CME reaches Earth, it leads to a geomagnetic storm. This can disrupt services, damage power grids and cause blackouts.

For instance, back in 1989, a powerful geomagnetic storm led to a major power blackout in Canada. As a result, around 6 million people were left in the dark for about 9 hours.

Solar flares can also result in disruption of services. The strongest and most intense geomagnetic storm ever recorded occurred in 1859. This was caused by a solar flare. Called the "Carrington Event and named after England's solar astronomer Richard Carrington who observed the activity through his telescope, the geomagnetic storm caused damage, disrupting the telegraph system on Earth. It also led to the aurorae, a result of geomagnetic activity, being visible in regions such as Cuba and Hawaii.

While telegraph networks are a thing of the past, our communications system and technologies can still be impacted by space weather. Even as most of the charged particles released by the Sun get shielded away due to Earth's magnetic field, sometimes space weather can affect us. We need to track the activities on the Sun's surface and understand them to protect the people and systems.

Any warning regarding bad space weather can help scientists send alerts and lessen the damage caused by it. Space agencies have observatories monitoring the Sun and detecting solar storms. These help in mitigating the effect of bad space weather.

Picture Credit :Google